Fiber optic cables are well known for connecting optical devices and systems. Some cables carry multiple fibers and have one or more plugs, such as connectors. “Pre-connectorized” cables have their connectors attached during manufacture, while others are terminated and have connectors attached upon installation. Cables known as patch cables, jumper cables, and break out cables are often relatively short and have one or more connectors at each end. In use, each connector will be placed within a port located in a piece of equipment, patch panel, another connector, etc.
As fiber optic equipment and networks become more common and more complex, the identification of proper plugs and sockets (into which the plugs are mated) for setting up and maintaining the systems accordingly becomes more complex. Therefore, indicia such as labels, hang tags, marking, coloration, and striping have been used to help identify specific fibers, cables, plugs, and/or sockets. While such indicia have been helpful in providing information to the craftsman setting up or servicing a system, further improvement could be achieved.
RFID systems have therefore been applied to fiber optic systems to provide information regarding fibers, plugs, and sockets. For example, RFID transponders (comprising an antenna and an RFID integrated circuit chip) have been attached to plugs and sockets for use in identification. The RFID integrated circuit chip stores information for RF communication. Typically, these RFID transponders have been passive, rather than active, so they communicate (by transmitting, reflecting, modifying, or otherwise sending RF signals) the stored information responsive to interrogation by an RF signal received by the RFID transponder antenna. An RFID reader comprising a transceiver that sends an RF signal to the RFID transponders and reads the responsive RF signals communicated by the RFID transponders could then interrogate the RFID transponders to determine stored information about the cable, plug, and/or socket. In some fiber optic connector systems, an RFID transceiver antenna is located near the socket for detecting an RFID transponder attached to the inserted plug, and the transceiver antenna further is connected to the remainder of the transceiver via wiring.
The various systems above generally rely upon a certain degree of proximity for operation. That is, the reader in the system would identify nearby RFID transponders, or would identify pairs of transponders close together (for example, on a plug and on a socket holding the plug), all within the read range of the reader. The read range could be designed to be small, for example for rows of readers mounted on adjacent sockets for reading only an inserted plug's RFID signal. Alternatively, the read range could be much larger, for example for handheld or room-size readers for reading multiple signals from one or more pieces of equipment.
However, such RFID systems have certain drawbacks. For example, the operation of such systems is dependent upon the relative proximity to a targeted item, which can lead to either difficult or inaccurate results, as signals may be received and/or communicated by unintended RFID transponders on items near the targeted item. Accordingly, the read range of a given RFID reader, whether incorporated into the socket housing or remote, can be a limiting factor. Further, if a plug were only partially inserted into a socket so as not to make a functional connection with the optical fiber(s), the RFID antennas in the plug and/or socket might inaccurately indicate the connection were made due to the proximity between the plug and the socket.
Moreover, when dealing with an entire panel of connectorized cables and sockets, it may not be practical or even possible to rely upon proximity, either plug-to-socket or reader-to-transponder, as a method of querying a targeted RFID transponder. In fact, the RFID transponders across the entire panel could respond to an RFID reader in certain situations, thereby providing no useful information as to identification of individual plugs and/or sockets of interest.
In such situations, a craftsman may need to separate a plug from the socket and panel to obtain information from the RFID transponder of the plug or socket, thereby breaking the fiber optic connection in the process. Such action adds a step to the process of identification in terms of unplugging or at least re-orienting objects in a certain way to avoid “false” readings from the panel due to proximity issues. Also, it may be necessary to disconnect the optical fiber plugs, possibly one after another, until a targeted optical fiber is found. Such serial disconnection can be even more undesirable when equipment is operating and disconnections cause problems for the users of the systems. In such cases, the whole system may have to be shut down just to allow for the identification of a single cable, even if sophisticated RFID equipment is in place. The process becomes more complex when extended to entire networks including multiple equipment housings, cables, etc., perhaps spread throughout a building.
It can also be difficult for the craftsman in the field to determine how or why a plug, cable, socket, or the like has failed or otherwise needs replacing. Again, identification of a single item within a group can be difficult, as well as identifying conditions leading to a particular issue. Conditions causing the problem could be transitory and no longer apparent or in effect when the craftsman arrives for service. Accordingly, providing more information to the craftsman for purposes of identification, troubleshooting, service, warranty, etc. would also be useful.
Therefore, a need exists for RFID technology that provides simple, reliable, and/or unobtrusive identification of one or more components and mapping of networks of components, including identification of location and past and/or present condition.